Combined chair seat/backrest



FIG. 1 is a perspective view of a combined chair seat/backrest showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left elevational view thereof; the opposite side being a mirror image of the shown.

FIG. 5 is a top plan view thereof; and,

FIG. 6 is bottom plan view thereof. 

The ornamental design for combined chair seat/backrest, as shown and described. 